The combined revenues from premiums at the nation's eight medium-size life insurers for the year that ended in March came to 6.045 trillion yen, a drop of 4.6 percent from the previous year, business reports showed June 10.

The total figure for the previous year excludes revenue for Nissan Mutual Life Insurance Co., which was ordered to suspend operations this April. The earnings reports for fiscal 1996 also indicated a widening gap among the firms, with Fukoku Mutual Life Insurance Co. increasing its premium income -- which for insurers is the equivalent of sales -- by 22 percent while Toho Mutual Life Insurance Co. saw its premium revenue fall 19.8 percent. Total assets at the eight companies came to 34.96 trillion yen, a 1 percent decline from the previous business year.

All the insurers except Fukoku saw outstanding contracts for group annuity policies continue to fall, as large buyers such as the Pension Welfare Service Public Corp. withdrew their money as the insurers failed to raise their minimum guaranteed return on the policies. As for pretax earnings, the eight firms altogether logged profits of 225.3 billion yen.